Dissertation > Excellent graduate degree dissertation topics show

Sythesis and Shape-Controlled Study of Copper/Cupreous Oxide Powders

Author: ZhangQiong
Tutor: ZhangJunJi
School: Dalian Jiaotong University
Course: Materials Science
Keywords: Copper Cuprous Oxide Hydrothermal Synthesis Liquid-Phase-ReductionSynthesis Morphology
CLC:
Type: Master's thesis
Year: 2013
Downloads: 22
Quote: 0
Read: Download Dissertation

Abstract

As an important class of inorganic functional materials, copper and copper oxide have a wide range of applications in the field of catalytic, electronic, magnetic storage record detection sensor, solar installed to replace the battery, defense and other technologies. The preparation process and the performance study which related to them has also become the focus of materials scientists in the past two decades. The purpose of this study is to develop economy, green synthesis process of copper and copper oxide powder and explore the formation mechanism, provide the basis for the shape-controlled synthesis of the powder material.In this paper, copper powder were synthesized by hydrothermal method, the effect of the amount of D-sorbitol, reaction temperature, reaction time, concentration of reactants on the phase composition and morphology of the products were studied firstly. It was found that:Cu+was initially formed and subsequently reduced to form highly pure copper when D-sorbitol served as reductant. So the intermediate product may have an impact on the final product. The reaction time have a significant impact on the phase composition and morphology of the obtained samples. The reduction reaction didn’t proceed completely when the reaction time was short. And the final products were a mixture of Cu, Cu2O and CuO whose morphology was spherical, hexagonaliked. Prolonging the reaction time to15h, flower-shaped pure Cu was obtained. If the reaction time was extended to16h, rod-shaped and spherical pure copper was obtained. When the reactant concentration was low, the resultant was mainly Cu, also contain a small amount of a mixture of Cu2O and CuO. When the concentrations of the reactants were high, the final product became flower-shaped copper.Copper powder was sythesised via liquid-phase reduction method with seqsodium hypophosphite as the reductant, and the main factors were investigated. The conclusions as followed, the amount of EDTA-2Na had a significant effect on the morphology of products which would have fine dispersity and morphology when the moral ration of Cu2+/EDTA is05. Elevated reaction temperature is conductive to generate pure copper. Cubic structure of copper with spherical, rod-like and triangular palatelike morphology were obtained whene the reaction temperature is among80℃to90℃,Finally, cuprous oxide powders were synthesized via liquid-phase reduction method with glucose as reductant under alkaline conditions. We found that the particle size of cuprous oxide decreased as the reaction temperature rised; NaOH concentration is low, Cu2O crystal spherical, with the rise of the concentration of NaOH, spherical and cubic mixed crystal Cu2O spherical, Cu2O the transition to the cubic polyhedron with the concentration of sodium hydroxide increased; using Cu(OH)2colloid as precursor, we got monodisperse spherical Cu2O particles whose average particle size is about1μm; using CuO as precursor, we got cubic polyhedral Cu2O particles whose particle size is uneven.

Sythesis and Shape-Controlled Study of Copper/Cupreous Oxide Powders

Abstract

Related Dissertations